[dolmen]

On MacOS:

   $ LANG=C cal -3
      May 2022             June 2022             July 2022        
    Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa  Su Mo Tu We Th Fr Sa  
     1  2  3  4  5  6  7            1  2  3  4                  1  2  
     8  9 10 11 12 13 14   5  6  7  8  9 10 11   3  4  5  6  7  8  9  
    15 16 17 18 19 20 21  12 13 14 15 16 17 18  10 11 12 13 14 15 16  
    22 23 24 25 26 27 28  19 20 21 22 23 24 25  17 18 19 20 21 22 23  
    29 30 31              26 27 28 29 30        24 25 26 27 28 29 30  
                                                31

[ginko]

Well, cal -3 shows the previous and next month, but I wanted this month and the next two months. I also wanted them arranged vertically and with week numbers. (And with weeks starting on Monday)